1. Field of the Invention
The present invention consists of a device for determining the elapsed time since an item of equipment was first activated, in particular, an item of equipment of an electrical or electronic nature.
2. Description of the Related Art
When items of electrical or electronic equipment are sold, the purchaser is normally granted a guarantee for the correction of any faults at no cost. If nothing is agreed to the contrary, the guarantee comes into force on the day the equipment is handed over. Consequently the manufacturer, the seller and the purchaser have a legitimate interest in documenting as accurately as possible the day the equipment is handed over or the day on which it is first activated.
The day on which the equipment is handed over is usually determined by the issue of a Guarantee Card with the hand-over date or by a dated receipt for payment. Problems can occur, however, if the issue of a Guarantee Card has been forgotten or the hand-over date has not been entered on the Guarantee Card. A further problem arises if there is no reference on the receipt to the Serial Number of the purchased item of equipment. Burden-of-proof problems affecting both the buyer and the seller are unavoidable. The manufacturers/sellers of equipment, therefore, go through a complex administrative procedure in order to be protected against unjustified claims against guarantee. Each item of equipment is provided with a Serial Number. The seller is obliged to fill out a Guarantee Card for each item sold on which the date of the hand-over and the Serial Number of the item of equipment must be recorded. When several thousand items of equipment are sold--a situation which is not unusual for wholesalers--the mere filling out of the relevant Guarantee Cards requires a very great deal of personnel time.
Moreover, the customers also have to take special administrative measures to ensure that the relevant Guarantee Card is available for each item of equipment. This procedure is very cost intensive in terms of personnel and prone to error.
Disclosure document DE 3428698 describes a device for the definite determination of the date upon which an item of equipment involved in entertainment electronics was first used, such that with the aid of a memory unit and a timing unit a situation is created where the equipment can only be used for the intended purpose if a date is entered. If this action is not carried out, the timing unit interrupts the operation of the equipment after a period of time. A disadvantage of this device is that the unit for determining the date of first activation must be connected to the switching arrangement of the equipment. Provision for this connection must be made at the time the equipment is being developed, or subsequent insertion is practically impossible.
Furthermore, this solution is not customer friendly as the customer is obliged to enter a date in order to prevent equipment being switched off automatically.
It is, therefore, the task of the present invention to propose a device which determines the time which has elapsed since a unit of equipment was first activated, which is simple in construction and operation, and can also be inserted without amendment into almost any other unit of equipment after manufacture. This invention must also determine the time which has elapsed since the equipment was first activated in a customer-friendly manner.